Snmp; Snmp Versions And Supported Mib - 3Com 7700 Configuration Manual

SNMP

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SNMP
The Simple Network Management Protocol (SNMP) has gained the most extensive
application in the computer networks. SNMP has been put into use and widely
accepted as the industry standard. It is used for transmitting management
information between any two nodes. In this way, network administrators can
easily search and modify the information on any node on the network. They can
also locate faults promptly and implement the fault diagnosis, capacity planning
and report generating. SNMP adopts the polling mechanism and provides the
most basic function set. It is most applicable to the small-sized, fast-speed and
low-cost environment. It only requires the unverified transport layer protocol UDP;
and is widely supported by many other products.
In terms of structure, SNMP can be divided into two parts, namely, NMS and
Agent. NMS (Network Management Station) is the workstation for running the
client program. At present, the commonly used NM platforms include Sun
NetManager and IBM NetView. Agent is the server software operated on network
devices. NMS can send GetRequest, GetNextRequest and SetRequest messages to
the Agent. Upon receiving the requests from the NMS, Agent will perform Read or
Write operation according to the message types, generate and return the
Response message to NMS. On the other hand, Agent will send Trap message on
its own initiative to NMS to report events whenever the device encounters any
abnormalities.
SNMP Versions and To uniquely identify the management variables of a device in SNMP messages,
Supported MIB SNMP adopts the hierarchical naming scheme to identify the managed objects. It
is like a tree. A tree node represents a managed object, as shown in the figure
below. Thus the object can be identified with the unique path starting from the
root.
Figure 4 Architecture of the MIB Tree
1
2
1
1
2
1
2
B
5 6
A
The MIB (Management Information Base) is used to describe the hierarchical
architecture of the tree and is the set defined by the standard variables of the
monitored network device. In the above figure, the managed object B can be
uniquely specified by a string of numbers {1.2.1.1}. The number string is the
Object Identifier of the managed object.